Vacuum operated fuel feeding apparatus



Dec. 1, 1931. a. s. BURTON 1,834,140

VACUUM OPERATED FUEL FEEDING APPARATUS 3 Sheets-Sheet 1 Dec. 1, 1931. c. s. BURTON 1,834,140

VACUUM OPERATED FUEL FEEDING APPARATUS Filed Oct. 24, 1929 :5 Sheets-Sheet 2 ,ZEaV 72501". (arZea xi'Zpza/o'zz.

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Dec. 1, 1931. c. s. BURTON 1,334,140

VACUUM OPERATED FUEL FEEDING APPARATUS Filed Oct. 24, 1929 3 Sheets-Sheet 3 I I l I Inflimfr' I (72 rles flz/rzfz &

Patented Dec. 1, 1931 PATENT OFFICE,

CHARLES S'. BURTON, OF OAK PARK, ILLINOIS VACUUK OPERATED FUEL FEEDING APPARATUS Appiication filed; October 24, 1929. Serial No. 402,204.

The purpose of this invention is to provide a vacuum feeding apparatus which can be operated by connectionwith a source of suction,as the intake manifold of the engine served,without valve control of the suction and without requiring the atmosphere inlet port to be materially larger than the suction port. The invention consists in the elements and features of construction shown and described as indicated in the claims.

In the drawings: Figure 1 is a vertical section of a vacuum tank embodying this invention.

Figure 2 is a detail elevation of the cooperating terminals of suction pipe and vacuum tank top having respectively suction port and atmosphere inlet. port, the suction pipe being shown in atmosphere inflow position. Figure 3 is a detail plan view on an enlarged scale of the parts shown inFigureQQ Figure 4 is a detail elevation of co-operating parts corresponding to those shown in Fi ure 2 in a modification consisting of furnishing the suction pipe with a vacuum booster. 1

Figure 5 is a detail top plan view showing a modified arrangement and mounting of the suction pipe on the vacuum chamber. Figure 6 is a detail side elevation of the modification shown in Figure 5.

Figure 7 is a view similarto Figure 4,

showing the form illustrated in Figures 5 and 6 provided with abooster. as inFigure 4.

Figure 8 is a sectional top'plan view showing in the sectional part a detail modific'a-' tion.

Figure 9 is a section at the line 99 on:

at the line 1212 on Figure 11.

Referring to the drawings in detail: A

customary form of vacuum tank'is shown comprising main outer and lower reserve fuel chamber, A, and lnner and upper vacuum top plan view, and Figure 12 a detail section a chamber, B, the latter having fuel supply connection, indicated at 20, and outflow fitting, seen at 21, with the customary form of outlet valve, 22. j

The top, 23, of the vacuum chamber has a 56 third port, 24, shown as formed through an outwardly projecting nipple, 25, represented as formed by being struck up from the sheet metal stamping which forms the vacuum chambertop. A suction pipe member, 30, is 60 shown extending horizontally above the vacuum chamber top which may be described as mounted flexibly or hingedly to the remainder, 31, of the suction pipe, which may be understood as extending from the dash of the vehicle upon which the vacuum tank is exteriorly mounted, to the intake manifold of the engine. 7

As illustrated, the hinged or pivotal connection of the suction pipe terminal member, 30, is effected by a flexible coupling sleeve, 33, which may be of rubber suitablyprepared for enduring the slight fuel vapor contact to which it may be exposed. The free end of the suction pipe member, 30, is bent downwardly, as shown at 35, and the down-turned end is finished to mate with and seat upon the upper end of the'nipple, 25, with the inlet port, 35, of said suction pipe member in junction with the port, 24, of the nipple.

A slender rod or wire, 36, is attached at its upper end to the free end of the suction pipe, 30, and for such attachment extends into the open end of said'pipe and from said attachment extends down through said third port, 24, of the vacuum chamber and to a guide bearing, 37, which may be most conveniently afforded by a spider at'the inlet end of the outlet valve fitting, 21.

A float, 40, is mounted slidingly on the rod, 36, between upper and lower stops, 41, 42, with which the rod is provided.

The operation of the structure as thus far described may be understood from the foregoing description to be as follows:

' Starting with the vacuum tank empty in both chambers, and assuming the suction pipe connected with a source of suction,.as the intake manifold of the engine,the suction pipe will be held by the weight of the m0 float with its inlet port, 31, in junction with the third port, 24, of the vacuum chamber.

The communication of suctionthrough the suction pipe to the vacuum chamber which will take place by reason of the mating and junction of the terminal and inlet port of the suction pipe with. the nipple and third port of the vacuum chamber producing a degree of vacuum in the latter suflicient to lift the fuel from the fuel source to the vacuum chamber, causes the latterto become filled withfuel to a depth at which the float, 40, is upheld against the upper stop, 41, with sufficient force to overcome the suction hold on the suction pipe, which, being lifted away from the nipple, 25, a short distance, leaves the third port, 24, of the vacuum chamber in free comv munication with the atmosphere instead of in communication with the source of suction; and thereupon the vacuum which has been produced in the vacuum chamber is quickly relieved by the free access of atmospheric pressure through the port, 24, admitting the liquid content of the vacuum chamber to be dumped,-i. e. delivered by gravity,+into the reserve chamber. And when the float, lowered by the lowering of the level of the liquid in the vacuum chamber, arrives at the lower stop, 41, it operates by its weight to retract the free end of the suction pipe into junction of its inlet port, 31, with the vacuum chamber port, 24. thus restoring the initial condition for lifting the fuel to refill the vacuum chamber; and the cycle of operation is thereupon repeated.

To ensure prompt and reliable action in the movement of the suction pipe under the control of the float as above described, and more especially to ensure its remaining out of position for registering its inlet port with the vacuum chamber: port, 24, until the float has descended into lodgement on the lower stop, 41, it is desirable to provide a snap action device, which is illustrated in familiar form indicated in entirety by the reference numeral, 60, and on account of its familiarity, requiring no specific description.

In Figure 4, the suction pipe is shown provided with what is commonly called a vacuum booster, consisting of a funnel-shaped mouth-piece, 38, constituting the air inlead to the relatively restricted'bore of the suction pipe, into which said inlead opens at the bend, that is to say, so that the airstream flowing in through the funnel mouthpiece and on through the suction pipe, is transverse to the air stream flowing in through the suction pipe inlet port proper. 35 This booster device operates in a well known manner for the purpose of increasing the suction operating at the port, 35", resulting from a given degree of suction operating through the suction pipe.

The operation of the structure as a whole for alternate inflow of fuel to and dischargefrom the vacuum chamber, is not afl'ected by the presence of the vacuum booster except as.

accordance with the familiar operation of such vacuum boosters.

In Figures 5 and 6, there is shown a slight modification of the construction and arrangement of the suction pipe, consisting in mounting it for rocking about its longitudinal axis, and furnishing it with a transversely extending branch leading to the terminal downbend and inlet port. In this form, the suction pipe member, which is thus mounted on the top of the vacuumehamber, is seen at 50, having a closed end, 51, journalled in a bracket, 52, and its opposite end swivelled with the coupling, 53, by which it is connected for continuity of its duct with the remainder of the suction pipe leading to the suction source. The transverse branch 54, having a down bent terminal, 54, and the inlet port terminal, 55, at the end of the latter, is arranged for junction of said port, with the third port, 24, of the vacuum chamber, as in the other form, and as seen in Figure 6.

This form is also desirably provided with a snap action, 60, as 'in the first described form; and it will be understood that this form may be furnished with the vacuum booster in a manner requiring no further illustration, the form in all details being identical with that shown in Figure 4.

The swivel joint between the parts 50 and 53 may desirably be provided with a suitable oiler as indicated at 56", Figures 6 and 7.

It is well understood that an advantage of having the vacuum chamber of a vacuum tank which derivessuction for itsloperation by suction connection with the intake manifold of the engine served in continuous suction connection with the manifold, ariseswfrom the fact that when the apparatus has a valve controlling the suction connection, which is open only, during the filling phase of the tank, and is closed during the emptying phase, the. variationin the fuel mixture in the manifold due to leaning by .the air drawn in from the vacuum tank. is liable to seriously interfere with the uniform operation of the engine, sometimes resulting in the engine being stopped when running at idling speed or without load; and this difliculty is reduced and substantially obviated in certain familiar forms of vacuum tank by leaving the suction port without a valve and continuously open, the suction port being necessarily in. that case very much restricted in comparison with the atmosphere inlet port to' In the present construction, as illustrated in the drawings, with the inlet/port of the suction pipe substantially equal to the third port of the vacuum chamber, since the latter port must be of sufiicient size to permit the prompt delivery of the fuel to the reserve chamber in the emptying phase, the suction inlet port of the same size mayadmit to the intake manifold an undesirably large amount of air in the phase of non-j imction of said suction inlet with the vacuum tank port; and under thesecircumstances the construction above described, if the vacuum chamber thirdport is large enough to permit desirably rapid delivery of the fuel from the vacuum chamber, may cause embarrassment in the running of the engine in a manner similar, but in certain respects opposite, to the embarrassment above mentioned which is experienced in the'operation of a vacuum tank having a suction controlling valve alternating with the atmosphere valve in opening and closing. Such embarrassment may arise from the fact that the air taken into the intake manifold when the suction inlet port is in junction with the vacuum chamber port, is to some extent charged with fuel vapor and thereby constitutes a fuel mixture, though usually quite lean, while in the other phase, that is, when the suction inlet port is out of junction with the vacuum chamber port, the air drawn into the vacuum chamber is wholly atmospheric without any fuel intermixture, so that the excessive leaning of the mixture in the intake manifold will occur during the emptying phase of the tank, instead of in the. filling phase.

This embarrassment may be avoided, and

the running of the engine rendered as steady and reliable as if there was no connection between the intake manifold and the vacuum tank, by providing means for reducing, without entirely interrupting, the access of air to the intake manifold through the suction pipe connectiion in the emptying phase of the tank, that is, in the period of separation of the suction inlet with the vacuum chamber port; and in Figures 8 and 9, a construction for this purpose is illustrated, consisting in connecting the suction pipe member which has the inlet port with the remainder of the suction pipe connection leading to the intake manifold by a swivel j'oint whose co-operating tubular elements have ports which overlap each other to a greater extent at the position of the suction pipe at which its inlet port is in junction with the vacuum chamber port, and which overlap each other to a less extent at the position of said suction pipe member at which its inlet port is out of junction with the vacuum chamber port.

Referring to the drawings in detail, which show the form of suction pipe illustrated in Figure 5, mounted for rocking about its longitudinal axis, and having a transversely projecting branch with'the inlet port at its downturned end This suction pipe member, 100, which is closed at both ends, is telescoped within a 00- operating sleeve member, 101, closed at its inner end forming an element of the fitting to which said remainder of the suctionpipe is connected at 102, the body, 103, of said fitting having its cavity of such diameter that the sleeve member, 101, mounted concentrically in the fitting, is surrounded by an annular space 110 in free communication beyond the inner end of the sleeve member with the remainder of the passage communicating with the suction pipe member, 30, leading to the intake manifold, and the two inter-telescoping parts, viz.,- the end portion of the suction pipe member, 100, and the sleeve member,l01, have ports, 104.- and 105, respectively, which are dimensioned for air fiow capacity substantially equal to that of the suction pipe inlet port, 106, and these ports are positioned for overlap up to said capacity of the posit-ion of the suction pipe member, 101, at which the suction inlet port is in junction with the vacuum chamber third port; but at the position at which said inlet port is out of junction with the vacuum chamber third port, said ports, 104 and 105, are lapped to a substantially less extent than the fully eapa-' city, as for example, one-third or one-qu an ter said full capacity.

Upon considering this construction it will be understood that at the position of junction of the suction inlet port with the vacuum tank third port, the engine suction derived from the intake manifold will very quickly develop vacuum in the vacuum chamber for causing thelatter'to be tilled; and that during the filling phase the air drawn into the intake manifold will be very substantially charged with fuel vapor, but that at the position of separation of the suction inlet port and vacuum chamber third port, the access of air' through the suction pipe to the intake manifold will be reduced to such a degree that in view of the vapor mixture with the air drawn in while the ports were registered, the fuel mixture resulting in the intake manifold in the two phases, will not be materially different. And it will be understood that the carbureter may be adjusted for taking into account the amount of air which will be drawn into the intake manifold in both phases, so that the running of the engine will not be materially disturbed in either phase.

may be considered desirable to cover or house the operating parts described as mounted upon the top of the vacuum chamber, and a construction for this purpose is shown in Figure 8, in which the outer member, A", of the tank is extended up above the top of the vacuum chamber to a height sufiicient to on compass the parts mounted on the top of the but latter, and a cap, C, is provided adapted to intake manifold of the engine, or any similar source of suction, by making the booster with a relatively large and wide mouthed funnel exposed to an air blast, as from a fan driven by the engine. In the case of the fuel feeding apparatus mounted for relieving an engine of a vehicle traveling at high speed, as for example, an aeroplane, such funnel being ex posed forwardly, will obtain an air current at high velocity through the booster duct which will develop a. high degree of suction through the transverse inleading nipple arranged to register with the nipple, 24, of the vacuum chamber.

Such adaptation of the structure to aeroplane service, or other situation at which high speed air current is available, is illustrated in Figures 10, 11 and 12, the booster being in Venturi form comprising a wide-mouthed, and correspondingly extended, funnel, 80, tapering to a constricted throat at 81, and thence Widening for outflow of air through a reversed funnel portion, 82, the suction pipe consisting of a branch, 84, leading ofi' transversely from the Venturi constriction, formed with a down bent terminal, 86, carrying the inlet suction port, 87, as in the form shown in Figures 5 and 6.

I claim 1. In an apparatus for the purpose indicated, a chamber having a liquid inlet port and a liquid outlet port, and a third port at the upper part; a suction pipe arranged for extending and leading to a source of suction having a terminal with an inlet port positioned and dimensioned for junction with said third port of the chamber, said terminal being movably mounted'on the chamber for movement to carry its said inlet port into and out of junction with said third port of the chamber; means arranged to be operated by change of level of theliquid content of the chamber operatively associated with said suetion terminal for moving the latter into and out of position of junction of its said inlet port with said third port of the chamber by the descent and rise of the float in the chamber to predetermined high and low levels;

whereby when said ports are in junction, said third port of the chamber becomes a suction port, and when said ports are out of junction, said third port becomes an atmosphere inlet to the chamber, and the rise of the float to the predetermined high level effects the conversion of said third port from suction port to atmosphere inlet.

2. The construction defined in claim 1 having the operating connections from the float to the suction terminal extending through said third port of the chamber.

3. The construction defined in claim 1, the suction pipe being mounted for vertical movement of the part having the inlet port for junction of said inlet port with said third port of the chamber.

4. The construction defined in claim 1 having the suction terminal mounted for pivotal movement about a point of support relatively distant from said inlet port.

5. The construction defined in claim 1 comprising a snap action device operatively connected to the suction terminal for snapping it into and out of port-registering position, and holding it yieldingly out of registering position.

6. The construction defined in claim 1 having a vacuum booster forming the terminal of the suction pipe, the port for junction with thecha-mber port being open laterally of the air duct of the booster.

7. The construction defined in claim 1 having a suction pipe carrying the suction terminal swivelled for rocking in its mounting on the chamber and having for leading to the suction inlet port a transversely projecting branch with a downwardly extending terminal at the end at which the inlet port is situated. 2

8. The construction defined in claim 1 havlng the suction pipe provided with means for reducing the flow capacity for air flow to the suction source by the movement of said suction pipe which carries the suction inlet port out of junction with the vacuum chamber third port.

9. The construction defined in claim 1, the suction pipe member which has the suction inlet port for its movement into and out of registration with said port, being connected with the remainder of the suction connection extending to the suction source by a swivel joint, said oint comprising two pipe elements inter engaged telescopingly, and having ports positioned and dimensioned for overlap with each other to a greater extent at the position of the first mentioned suction pipe member at which its inlet port is in junction with the vacuum chamber third port, and for such overlap to less extent at the position of the first mentioned member at which the suction inlet port is removed from junction with the vacuum chamber port.

In testimony whereof, I have hereunto set my hand at Chicago, Illinois,'this 22nd day of October, 1929.

CHARLES S. BURTON. 

